Fogging on the windshield is caused by the contact of air at different temperatures. In summer it forms when the hot outside air touches the cold window, while in winter it develops when the warm air of the passenger compartment reaches the cold surface of the glass. Understanding this mechanism allows you to eliminate fogging in the correct way according to the season and to take preventive measures to prevent it from forming, which saves a lot of time.
Steps
Method 1 of 3: Warm Weather
Step 1. Reduce the intensity of the air conditioner when the outside temperature is warm
If the windshield fogs up in the summer, you can adjust the air conditioning system; in this way, the internal temperature increases making it similar to the external one. You can also open the windows slightly to allow air to enter and prevent the cabin heat from becoming oppressive.
Step 2. Activate the wiper blades
If condensation has formed on the outside of the windshield (which happens in summer), you can eliminate it with wipers; set the speed to minimum and let them do their job.
Step 3. Open the windows
This is a quick solution to make the internal temperature similar to the external one; lower the windows as far as possible to allow warm air to enter the car.
Method 2 of 3: Cold Weather
Step 1. Change the air source
Most vehicles are equipped with buttons that allow you to simply circulate the air already present in the passenger compartment or to suck it in from the outside; if your windshield is fogging up, change these kinds of settings so that fresh air gets in. Look for the button that shows the image of a car with an arrow pointing towards the car itself; touch it so that the light it is equipped with turns on.
Alternatively, press the button that shows the image of a car and a circular arrow to turn off the relative warning light; by doing so, you deactivate the indoor air recycle function
Step 2. Reduce the core temperature
Since fogging is caused by the difference in air temperature, by cooling the passenger compartment you can reduce this discrepancy and consequently the condensation on the glass; turn on the fan at maximum speed and lower the temperature to a bearable minimum.
This is the quickest but also the least comfortable method, so be prepared to shake a little
Step 3. Activate the defrost vent with cold air
This is directed towards the windshield, but the air it emits must have a temperature similar to the outside one; such forethought allows you to get rid of the fogging.
Method 3 of 3: Avoid Windshield Fogging
Step 1. Use silica-based cat litter
Fill a sock with this substrate and tie the end with string. Then place one or two of these "bundles" in the front of the dashboard to absorb internal humidity during the night; this little trick prevents condensation from forming.
Step 2. Smear some shaving cream on the crystal
Use a product that increases in volume when you spray it from the can, apply it to a soft cloth and spread it all over the windshield. Then take a clean, dry rag to wipe away any residue; in this way, you create an "anti-fog" barrier.
Step 3. Lower the windows if possible
If the car is hospitalized in a safe area, you can open the windows for about 1 cm; by doing so, outside air can enter preventing the windshield from fogging.
